1. Technological Field
The present invention relates to a semiconductor arithmetic circuit, and in particular, relates to an arithmetic circuit which is capable of conducting rapid, highly accurate calculations with respect to analog and multivalue data.
2. Background Art
In recent years, in concert with advances in computer technology, striking progress has been made in data processing technology. However, where attempts have been made to conduct the flexible type of data processing of which human beings are capable, it has seemed essentially impossible to obtain an arithmetical result in real time using present day computers. A reason for this is that the data which human beings deal with in the course of their everyday lives are analog data, and firstly, there is enormous amount of such data, and additionally, these data are imprecise and unclear. The conversion of the entirety of an extremely large amount of analog data into digital values, and the conducting in serial fashion of strictly unique digital operations present problems for present day data processing systems.
Image processing is an example of this. For example, if a screen is rendered in terms of a 500.times.500 2-dimensional pixel array, the total number of pixels is 250,000, and if the intensity of the three colors red, green, and blue is expressed in 8 bit terms for each pixel, the amount of data required for one static screen image is 750,000 bytes. The amount of image data increase with time when the image is moving. Let us consider data processing in which, under these circumstances, a search is made, among an extremely large number of screens accumulated in the past, for that screen which is most similar to an incorporated screen. This type of processing may seem simple at first glance, but it is necessary to deal with the analog vectors which constitute the screen data, to calculate the distance between analog vectors, and to select the shortest distance. If an attempt is made to realize such processing using a computer, it is first necessary to convert all the analog vectors into digital vectors, and then to conduct arithmetical operations in serial fashion, so that even if a present day super computer is employed, it is impossible to manipulate this large amount of "1" and "0" data and to carry out screen recognition and analysis in real time. In order to overcome these problems, efforts have been made to realize data processing which is similar to that of human beings by inputting real world data in analog format in an unchanged manner, and conducting operations and processing in the analog format. This approach is most appropriate for real-time processing; however, this method has not yet been realized, and there exists at present no semiconductor arithmetic circuit which is capable of conducting such operations in real time and in a highly accurate manner.